The invention relates to a fuel injection pump for internal combustion engines which is provided with a housing as well as a pressure operated adjusting piston correlated with a chamber in said housing and a remotely positioned axially disposed restoring spring arranged to cooperate with said piston. Also included therein are a control plunger disposed coaxially with said adjusting piston, first means on said control plunger arranged to cooperate with second means on said adjusting piston and thereby adapted to control fluid flow into and out of said pressure chamber, whereby the control plunger is displaceable relative to the adjusting piston against the force of a restoring spring.
As a result of the increasing requirements now being made for nontoxicity in exhaust gas, the engine manufacturers are increasingly demanding of the manufacturer of injection pumps a type of pump which will meet the increasing standards all of which present the manufacturer of the pumps with great difficulties, particularly because the pump must be economical to produce and a certain cost structure must not be exceeded. Thus, the engine manufacturer asks not only that the injection timing adjuster be adjusted in proportion to engine speed, and, if possible with a supplementary adjustment for starting speeds, but in addition that there be a pressure sequence in the injection timing adjusters which cannot be attained in known apparatuses.